My BOV has a diesel engine (Peugeot Indenor 2.1).
Diesel engines tend to operate at lower RPM's, and diesel fuel has superior lubricating properties. They're more reliable, with no spark plugs, no ignition coil, no distributor, no plug wires, and no oxygen sensors in the exhaust system. They could run on other types of (vegetable) oil in a pinch, although that's still illegal here (Netherlands) for tax reasons.
Diesel is less volatile than gasoline, with a far longer "shelf life". And it's much, much safer to store.
(Gasoline is more dangeroush than dynamite; it has a low flashpoint. A spark will set ot of!)
I try to keep a small supply on hand, and think old-fashioned "Jerry cans" are the best storage containers.
They're rugged, stackable, easy to pour from, and they don't "breath" like plastic containers.
A 20 liter Jerry Can equals approximately 200 kilometer in my BOV.
There are two common problems with storing diesel fuel:
1. It begins to oxidize as soon as it leaves the refinery.
Gums and sediments that clog fuel filters form.
The process can be slowed by keeping it cool and by adding stabilizers.
2. Water, usually from condensation in the empty part of the storage container, is the medium for algae growth.
A slime that will again clog fuel filters results.
Adding biocide will prevent algae growth, but better yet is to keep it in a sealed, full container and in a stable temperature to prevent water from condensation in the first place.
Those who store large amounts of diesel for long periods (deep water sailors, the military, power plants with back-up generators) periodically test and "polish" their fuel, filtering and adding additional stabilizers.
For Preppers, rotating stocks is more practical, but funnels with built-in filters are available.
Exxon's website says that: "If you keep it clean, cool and dry, diesel fuel can be stored 6 months to 1 year without significant quality degradation.
Storage for longer periods can be accomplished through use of periodic filtrations and addition of fuel stabilizers and biocides."
Chevron says: "those who store diesel fuel for a prolonged period, i.e., one year or longer, can take steps
to maintain fuel integrity. The steps below provide increasing levels of protection:
1. Purchase clean, dry fuel from a reputable supplier and keep the stored fuel cool and
dry. The presence of free water encourages the corrosion of metal storage tanks and
provides the medium for microbiological growth.
2. Add an appropriate stabilizer that contains an antioxidant, biocide, and corrosion inhibitor.
3. Use a fuel quality management service to regularly test the fuel, and, as necessary,
polish it – by ﬁltration through portable ﬁlters – and add fresh stabilizer."
BP says: "Under normal storage conditions diesel fuel can be expected to stay in a useable condition
• 12 months or longer at an ambient of 20ºC.
• 6-12 months at an ambient temperature higher than 30ºC.
As diesel gets older a fine sediment and gum forms in the diesel brought about by the
reaction of diesel components with oxygen from the air.
The fine sediment and gum will block fuel filters, leading to fuel starvation and the engine stopping.
Frequent filter changes are then required to keep the engine going.
The gums and sediments do not burn in the engine very well and can lead to carbon and soot deposits on injectors and other combustionsurfaces."
Diesel fuels are blended for different seasons and regions. "Summer" diesel may cloud or gel at cold temperatures.
From BP: "Always purchase fuel to replenish stocks in the winter season.
This will ensure that the fuel will not cause wax problems whatever season it is used."
According to Exxon: "Non-winterized diesel fuel will not generally cause problems as long as temperatures are at or above -10°C."
So the basic strategy boils down to:
1. Buying "fresh" fuel (the quotation marks are because it's probably already several weeks old by the time it works it's way from the refinery to us consumers).
2. Topping off storage containers, leaving just enough headspace for expansion and contraction, but not much for condensation.
3. Keeping it dry and cool. Heat speeds deterioration, temperature swings will cause condensation.
4. Adding a stabilizer to slow oxidation if storage in warm temperatures or beyond a year is anticipated.
5. Adding a biocide to prevent algae growth (or better yet, keep it in a sealed, full container and in a stable temperature to prevent water condensation in the first place).
6. Rotating stocks every winter.
7. When in doubt, filtering.
Further reading shows that diesel in normal or ideal conditions could be stored for more than to or even 5 years without additives; antioxidant, biocide, and corrosion inhibitor.